GUANTANAMO BAY, Cuba — Maybe they should change LeBron James’ number to 007.

The lawyer for an al Qaeda prisoner at Gitmo yesterday disclosed a secret so explosive, it could rock the very foundation of the NBA: His client thinks the hoop star is a “very bad man’’ for defecting from Cleveland to Miami.

Military defense lawyer Kevin Bogucki — noting that Muhammed Rahim’s opinion of the hoops star was treated as top secret for two months — said the prisoner wrote a note criticizing the star’s decision to leave the Cleveland Cavaliers for the Miami Heat in 2010.

“LeBron James is a very bad man. He should apologize to the city of Cleveland,” Bogucki quoted the note as saying.

He did not say who got the note.

Rahim has not been charged with a crime — but because he was previously held and interrogated by the CIA, every word he writes or utters is presumed to be “Top Secret” unless a government Security Classification Review Team declares it’s safe to release.

“It took that classification authority approximately two months to determine that my client’s opinion of LeBron James did not pose a grievous threat to national security,” said Bogucki, who did not indicate when the note was written.